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JPS574027A Expired / Lapsed JP ⏱️ 0.0 years remaining

Exposure control device for camera

Assignee: Minolta Co Ltd
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Filing: 1980-06-09
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Granted: —
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Expires: 2000-06-09
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Abstract

Abstract PURPOSE: To obtain always exposure by correcting the exposure control errors owing to the differences in the reflectivities of a film face based on photometric output. CONSTITUTION: A comparator 28 which compares the output of a photometric integrating circuit 24 including a photodetector 12 receiving the reflected light from a shutter curtain plane and a film plane and the prescribed output of a reference voltage circuit 54 is provided, and when both outputs attain a prescribed relation, exposure is ended. In this case, a subtractor 50 which operates the difference between the photometric output X corresponding to the output from the photodetector 12 and the output Y delaying 48 said output X by a prescribed time, and an integrating circuit 52 which outputs correction voltage by integrating the subtracted output F are provided, and the correction voltage as reference voltage H is introduced into the comparator 28, whereby the exposure control errors owing to the difference in the reflectivities of the film face are corrected. COPYRIGHT: (C)1982,JPO&Japio

Inventors

  • 👤 Kazuo Kimura

Bibliographic Details

Application Number —
Jurisdiction JP
Data Source google_patents
Last Synchronized 2026-11-09 17:18
CPC Classifications
G; G03; G03B; G03B7/00; G03B7/08; G03B7/081; G03B7/083

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

JPS54151029A Cited
JPS5657028A Cited

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